Pharmaceutical drugs end up in our drinking water, and no one really knows what to do about it.

Taking pharmaceutical drugs is essentially not a choice anymore: our drinking water is loaded with drugs according to a new Environmental Protection Agency (EPA) study. The way these drugs we get into our water is simple: people take them, use the bathroom, flush their drugs away, and then the water gets filtered, cleaned and recirculated. Over time, the residue of drugs in our water has built up and now there are more drugs in our water than anyone anticipated, according to the EPA study, to be published in January in the journal Environmental Pollution, but obtained in advance by The New Republic.

“We were surprised to find that many drugs occurring across all the wastewater plants,” said Mitchell Kostich, the EPA research biologist who led the study. “We were also surprised to see so many drugs of a particular class—the high blood pressure medications—appear at those levels across the board.”

Filtering drug residue out of our water is difficult, and it is not clear what should be done about the ever-increasing pharmaceutical cocktail in our reservoirs.

The study tested 50 large wastewater treatment plants, testing them for 56 drugs from Ibuprofen to Oxycodone. Over half of the plants had detectable levels of over 25 drugs.

That there needs to be some kind of government intervention here is clear enough. What form that would take is far from clear.